Magnetoencephalography: physics, techniques, and applications in the basic and clinical neurosciences.

Magnetoencephalography (MEG) is a technique used to measure the magnetic fields generated from neuronal activity in the brain. MEG has a high temporal resolution on the order of milliseconds and provides a more direct measure of brain activity when compared with hemodynamic-based neuroimaging methods such as magnetic resonance imaging and positron emission tomography. The current review focuses on basic features of MEG such as the instrumentation and the physics that are integral to the signals that can be measured, and the principles of source localization techniques, particularly the physics of beamforming and the techniques that are used to localize the signal of interest. In addition, we review several metrics that can be used to assess functional coupling in MEG and describe the advantages and disadvantages of each approach. Lastly, we discuss the current and future applications of MEG.

The role of mainstreamness and interdisciplinarity for the relevance of scientific papers.

Is it possible to tell how interdisciplinary and out-of-the-box scientific papers are, or which papers are mainstream? Here we use the bibliographic coupling network, derived from all physics papers that were published in the Physical Review journals in the past century, to try to identify them as mainstream, out-of-the-box, or interdisciplinary. We show that the network clusters into scientific fields. The position of individual papers with respect to these clusters allows us to estimate their degree of mainstreamness or interdisciplinarity. We show that over the past decades the fraction of mainstream papers increases, the fraction of out-of-the-box decreases, and the fraction of interdisciplinary papers remains constant. Studying the rewards of papers, we find that in terms of absolute citations, both, mainstream and interdisciplinary papers are rewarded. In the long run, mainstream papers perform less than interdisciplinary ones in terms of citation rates. We conclude that to avoid a unilateral trend towards mainstreamness a new incentive scheme is necessary.

The mystery of our mathematical universe.

Why is it that fundamental laws discovered through pure mathematics have been able to describe the behavior of our physical world with such precision? Given that the physical universe is composed of mathematical properties, some have posited that mathematics is the language of the universe, whose laws reveal what appears to be a hidden order in the natural world. Physicist S. James Gates, Jr. and science writer Margaret Wertheim explore the uncanny ability of mathematics to reveal the laws of nature.

Multiscale impact of researcher mobility.

International mobility facilitates the exchange of scientific, institutional and cultural knowledge. Yet whether globalization and advances in virtual communication technologies have altered the impact of researcher mobility is a relevant and open question that we address by analysing a broad international set of 26 170 physicists from 1980 to 2009, focusing on the 10-year period centred around each mobility event to assess the impact of mobility on research outcomes. We account for secular globalization trends by splitting the analysis into three periods, measuring for each period the effect of mobility on researchers' citation impact, research topic diversity, collaboration networks and geographical coordination. In order to identify causal effects we leverage statistical matching methods that pair mobile researchers with non-mobile researchers that are similar in research profile attributes prior the mobility event. We find that mobile researchers gain up to a 17% increase in citations relative to their non-mobile counterparts, which can be explained by the simultaneous increase in their diversity of co-authors, topics and geographical coordination in the period immediately following migration. Nevertheless, we also observe that researcher's completely curtail prior collaborations with their source country in 11% of the cross-border mobility events. As such, these individual-level perturbations fuel multiscale churning in scientific networks, e.g. rewiring the connectivity of individuals and ideas and affecting international integration. Together these results provide additional clarity on the complex relationship between human capital mobility and the dynamics of social capital investment, with implications for immigration and national innovation system policy.

New Horizons in Advocacy Engaged Physical Sciences and Oncology Research.

To address cancer as a multifaceted adaptive system, the increasing momentum for cross-disciplinary connectivity between cancer biologists, physical scientists, mathematicians, chemists, biomedical engineers, computer scientists, clinicians, and advocates is fueling the emergence of new scientific frontiers, principles, and opportunities within physical sciences and oncology. In parallel to highlighting the advances, challenges, and acceptance of advocates as credible contributors, we offer recommendations for addressing real world hurdles in advancing equitable partnerships among advocacy stakeholders.

Reengineering the Tumor Vasculature: Improving Drug Delivery and Efficacy.

A solid tumor is like an aberrant organ - comprised of cancer cells and a variety of host cells embedded in an extracellular matrix - nourished by blood vessels and drained by lymphatic vessels. In its journey from the blood stream to cancer cells, a therapeutic agent must cross the vessel wall and the extracellular matrix that cancer cells are ensconced in. Growth of tumors in a confined space along with deposition of matrix components, including collagen (yellow) and hyaluronan (pink), increases 'solid stress', which compresses blood and lymphatic vessels and impairs their function. The leakiness of tumor vessels also impairs tumor blood flow and increases 'intratumor fluid pressure'. The abnormal blood flow not only impedes drug delivery, but the resulting hypoxia also aids tumor invasion, metastasis, immunosuppression, inflammation, fibrosis, and treatment resistance. Engineers and physical scientists have dissected the molecular, cellular, and physical mechanisms underlying these abnormalities and developed a number of strategies to reengineer the tumor microenvironment to overcome these barriers and thus improve delivery and efficacy of treatments. Finally, these strategies have been translated from bench to bedside for treatment of cancer and have the potential to improve the treatment outcome for many diseases characterized by an abnormal microenvironment.

The NCI Physical Sciences - Oncology Network.

Nastaran Zahir is Associate Director of the Physical Sciences - Oncology Network in the Division of Cancer Biology at the National Cancer Institute. Dr. Zahir coordinates cross-cutting efforts to integrate physical sciences perspectives with cancer research by fostering transdisciplinary research collaborations, supporting education and outreach programs, and promoting resources for data sharing and biospecimen standards.

Particle Physics in High School: A Diagnose Study.

The science learning process improves when the contents are connected to students' lives. Particle physics has had a great impact in our society in the last years and has changed the theoretical picture about matter fundamental dynamics. Thus, we think that academic contents about matter components and interactions should be updated. With this study we aim to characterize the level of knowledge of high school students about this topic. We built a test with questions about classical atomic models, particle physics, recent discoveries, social implications and students opinions about it. Contrary to our first suspicion, students' answers show a high variability. They have new physics ideas and show a great interest towards modern concepts. We suggest including an updated view of this topic as part of the curriculum.

Let there be more light / Que haya más luz

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Universality of Citation Distributions for Academic Institutions and Journals.

Citations measure the importance of a publication, and may serve as a proxy for its popularity and quality of its contents. Here we study the distributions of citations to publications from individual academic institutions for a single year. The average number of citations have large variations between different institutions across the world, but the probability distributions of citations for individual institutions can be rescaled to a common form by scaling the citations by the average number of citations for that institution. We find this feature seems to be universal for a broad selection of institutions irrespective of the average number of citations per article. A similar analysis for citations to publications in a particular journal in a single year reveals similar results. We find high absolute inequality for both these sets, Gini coefficients being around 0.66 and 0.58 for institutions and journals respectively. We also find that the top 25% of the articles hold about 75% of the total citations for institutions and the top 29% of the articles hold about 71% of the total citations for journals.

The one and the many: the search for unity in nature.

The essence of physical reality-what the world consists of-has been a heated focus of contention for millennia. First with philosophers and then with physicists, the debate has been polarized since the beginning: while those loosely known as Platonists search for an underlying unity in nature, others caution that such unity is unachievable in practice and in principle. In this essay, we review both positions, arguing strongly for the latter in anticipation of experimental results from the Large Hadron Collider, the particle accelerator from the European Center for Nuclear Research. We further argue that, for the first time in history, the material essence of reality could be determined from an empirical standpoint as opposed to a purely dialectic one, settling the age-old debate.

After the Greeting: Realizing the Potential of Physical Models in Cell Biology.

Biophysics is increasingly taking center stage in cell biology as the tools for precise quantifications of cellular behaviors expand. Interdisciplinary approaches, combining quantitative physical modeling with cell biology, are of growing interest to journal editors, funding agencies, and hiring committees. However, despite an ever-increasing emphasis on the importance of interdisciplinary research, the student trained in biology may still be at a loss as to what it actually means. I discuss here some considerations on how to achieve meaningful and high-quality interdisciplinary work.

The origins of the universe: why is there something rather than nothing?

Perhaps the greatest mystery is why the universe exists in the first place. How is it possible for something to emerge from nothing, or has a universe in some form always existed? This question of origins-both of the universe as a whole and of the fundamental laws of physics-raises profound scientific, philosophical, and religious questions, culminating in the most basic existential question of all: Why are we here? Discussion of this and related questions is presented in this paper.